Wireless tracking systems are often used in large-scale military and commercial transportation applications. Recently, miniaturized tracking systems are being employed in various consumer and medical fields. As an example, recent trends in video gaming software now take advantage of controller position data that reflect movement of the controller relative to the console. Position detection enables the video game software to render images based on the controller position during gameplay. This enhances the user experience in a variety of ways.
One proposal for a game console tracking system employs multiple cameras facing a user. Gestures made by the user may be captured by the cameras and processed to render a depth of field that may be correspondingly analyzed to determine the controller position with respect to the cameras. A further example also utilizes a user-facing camera, but determines position based on the movement of an object, such as a colored illuminated ball, mounted to the controller that exhibits a detectable brightness that highly contrasts the brightness associated with an ambient room environment. Limitations of the camera approach often include [1] cost; [2] image processing complexities and associated burdens; [3] X-Y dimension pixel density resolution constraints; and [4] Z dimension resolution inconsistencies when compared to the X-Y dimensions.
For medical applications, tracking a position of, for example, a catheter being positioned in a patient, may involve the use of expensive imaging equipment. Moreover, for certain medical treatments, such as radiation therapy for cancerous tumors, pinpointing a precise location of a tumor, even during body movements, can be a very challenging task in an effort to reduce irradiating normal tissue.
Although each of the proposals noted above work well for their intended applications, it would be desirable to have a less costly and more straightforward approach to determining a target's position in absolute space.